"Light cannot be seen without shade. Shade cannot be seen without light."

By moonlight, we see in black and white. We cannot see colors. There is something fascinating and valuable about seeing the world that way. We see only what is essential. We see form emerging from a sea of blackness. . . . We can look at the world so familiar by daylight and see it anew in the black and white of moonlight. You see yin and yang. . . The day warms, the night cools. The sun moves over a hill, changing the face from brightness to shadow. Stand in the middle of a forest and watch all the shadows and sunlight shift second by second. You see yin and yang. - Deng Ming-Dao, The Lunar Tao (edited)